check it priveleges stupid really its just an alternative to normal used in some contexts not to offend people who dont like that whats normal isnt them like a transgendered person may be offended by you calling nontrannies normal because it makes it implicit that the tranny is not or worse the exact opposite a freak so cis is supposed to be a term to avoid offense by being a way to say normal without saying normal its also a favorite insult of tumblrites ironically